How deep is the seabed there anyway?
The locus of "French Warship" (LaPLace?) at 19:49:56z was 33° 25'N 29° 14'E. The water depth at that point is 3,024m (9,921').
Call it 10,000' in old money.
Think in terms of flying at FL100 and trying to find a sound, somewhere in a hundred square mile search zone below you, which to the human ear in air is pretty much like the sound volume and pitch of clacking of the backs of two teaspoons together.